Sharpening mechanism for slicing machines



Aug, 25, 1936. 1 I F x I 2,052,367

I SHARPENING MECHANISM FOR SLICING MACHINES Filed April 2, '1954 4 Sheets-Sheet 2 LINE OF KNIFE INVENTQR1 JOSEPH FOLK BY @ZF K Aug. 25, 1936. J FOLK 2,52,367

SHARPENING MECHANISM FOR SLICING MACHINES Filed April 2, 1934 4 Sheets-Sheet 3 INVENTORI JOSEPH FOLK J. FOLK SHARPENING MECHANISM FOR SLICING MACHINES Aug. 25, 1936.

4 Sheets-Sheet 4 Filed April 2, 19.34

INIVENTOR= JOSEPH FOLK AT T'YS.

Patented Aug. 25, 1936 UNITED STATES PATENT OFFIQE SHARPENING MECHANISM FOR SLICING ll LACHENES Application April 2, 1934, Serial No. 718,584

3 Claims.

This invention relates to slicing machines, and particularly to sharpening mechanism for slicing machine knives. The primary object of the present invention v is -to provide new and improved sharpening mechanism for slicing machine knives, the mech-.

anism having a sharpening stone and a burr removing stone arranged in position relative to the knife so as to normally be out of contact therewith, but capable of being moved into sharpening position by shifting the housing in a counter-clockwise direction against the urging action of a spring.

Another object is to provide a slicing machine knife sharpening mechanism which has a positively positioned sharpening stone capable of having adjustment relative to its housing, which has a resiliently mounted burr removing stone also capable of adjustment, and which is so constructed and arranged so that the entire sharpening mechanism may be adjusted in respect to the 1 knife.

A still further object of the invention is to provide sharpening mechanism which is positive and efficient in operation, which is constructed and arranged to attain the utmost in sanitation, which is positioned in non-operative position, but which can be moved into operative position by a mere twist of the supporting spindle, which is strong and durable in construction, and which can readily and economically be manufactured.

A still further object of the invention is to provide sharpening mechanism comprising a grinding stone and a burr removing stone each of which is mounted on a vertical spindle out of the way of the knife and then moved 180 to sharpening position, each grinding stone being resiliently mounted, there being manually operated means for axially shifting the spindles upon which the stones are mounted. The stones are so constructed and arranged that the grinding stone will engage the knife first and be moved away from the knife first, while the burr removing stone will be applied last and removed last.

Numerous other objects and advantages will be apparent throughout the progress of the following specification;

The accompanying drawings illustrate a selected embodiment of the invention, and the views therein are as follows:

Fig. l is a detail elevation of a slicing machine looking from the right-hand side of the machine toward the knife, and embodying the invention.

Fig. 2 is a detail elevation looking in a direction opposite to Fig. 1.

Fig. 3 is a detail vertical sectional view on the line 3-3 of Fig. 1.

Fig. 4 is a detail sectional view on the line 5 4-4 of Fig. 2.

Fig. 5 is a detail transverse sectional view on the lines 55 of Figs. 4 and 6.

Fig. 6 is a longitudinal vertical section on the line 66 of Fig. 4'.

Fig. 'I is a detail elevation partly in section showing a modified form of grinding mechanism.

Fig. 3 is a detail plan View of the sharpening mechanism with the normal non-sharpening position being shown in dotted lines. 15

Fig. 9 is a detail sectional view through the grinding stone on the line 9--9 of Fig. 8.

Fig. 10 is a detail vertical sectional view on the line Iii-l0 of Fig. 8.

Fig. 11 is a detail bottom plan view showing the stones moved out of their normal sharpening position and when the operating lever has been operated.

Fig.'l2 is a view similar to Fig. 11 but shows the stones in their normal and grinding position. 25

Fig. 13 is a detail sectional view through the burr removing stone taken on the line I3-I3 of Fig. 8.

Fig. 14 is a detail transverse sectional view on the line I i-44 of Fig. 10.

The particular slicing machine herein shown for the purpose of illustration comprises a base It] having a carriage ll mounted thereon, and adapted for longitudinal reciprocation thereof. The carriage II is provided with a substance tablel2, with which there cooperates a pusher plate I3 for urging substance on the substance table l2 against a gauge plate l4. A knife l5 which may be electrically driven is adapted to cut slices from the substance on'the substance table [2. The knife I5 is rotatably mounted in a knife supporting bracket it, which may comprise a part of the housing for the knife or the knife guard. A knife guard ii is adapted to extend about the periphery of the knife at the side opposite the operator, as clearly shown in Fig. l.

A vertical spindle I8 is slidably supported in the member l6 and carries at its upper end a housing IS. The housing I9 comprises a body 20 having a cover 2|. The body 20 and its cover 2! are fastened together by a screw 22, Figs. 3 to 6, passing through the cover 2|, and threadedly engaging a boss 23 formed in the part 29,

the two parts being held in proper alignment by a dowel pin 22, Fig. 4.

The housing I9 is mounted in such a position with respect to the knife bracket that the joint line 24 between the body and the cover is approximately in line with the knife cutting edge.

A sharpener stone 25 is arranged on one side of the knife, and constitutes the grinding stone, while a second stone 26 is arranged on the other side of the knife and constitutes the burr removing stone. The sharpener stone 25 is mounted on a shoulder spindle 21 and held by a screw 28. The spindle 27 is rotatably assembled in a sleeve 29, which is axially adjustable in a bearing 30 in the housing, Spindle 27 is axially held in the sleeve 29 by a washer 3i and a screw 32. A set screw 33 looks the sleeve 29 in the bearing 30 after the sharpener stone 25 has been properly adjusted in relation to the knife.

The burr removing stone 20 is fastened to a spindle 34 by a screw 35, and this spindle is rotatably mounted in a sleeve 36, which is axially movable in a bearing 3'! formed in the sharpener body housing I9. The spindle 3t is held against axial movement in the sleeve 36 by a washer 38 and a screw 39. The lower wall of the bearing 31 is slotted as shown at 40, Fig. 3, and a pin ll which is fastened in the sleeve protrudes downwardly through the slot. 4. The pin 4| is connected by a tension spring 42 to an anchor pin 43 in the housing.

The sharpener body housing I9 is pivotally fitted to the vertical spindle or pin I0, which is clamped at its lower end by a set screw 34 to the knife bracket I6. The pivotal movement of the sharpener body housing IS on the pin or spindle I8 is limited by a screw 45, Fig. 5, which is threaded into the spindle or pin I8 and by a stop pin 46, which is inserted in the housing parallel and adjacent to the pin or spindle I8. A torsion spring 41 is anchored on the set screw 45, and its coils surround the vertical pin or spindle I8. The free end 48 of the spring 41 braces against the inner side of the housing I9, and tends to force the housing in a counterclockwise direction until the set screw abuts the stop pin 46. In this latter position, the two sharpener stones have a sufficient clearance with the knife on its respective sides, Fig. 5.

When the sharpener housing I9 is turned in a clockwise direction on the pin or spindle I8, the two sharpener stones approach opposite sides of knife 15 in such a way that they will touch simultaneously. Inasmuch as the bearing 29 of the sharpener stone 25 is anchored in the sharpener housing I9, the sharpener stone 25 may be pressed against the side of the knife with considerable force to speed up the sharpening process of the knife while the burr removing stone 26 is applied with an even constant force due to the resiliency of the spring mounting. In other words, when the housing is turned clockwise, both the stones will come in contact with the knife, and while considerable manual pressure may be employed, all of the pressure will be directly applied to the sharpener stone 25. The pressure of the burr removing stone 26 will be much less and more constant and even, due to the slot and pin connection 40, 4! respectively, and the tension spring 42. This resilient engagement of the burr removing stone with the knife occurs as soon as the housing is moved in a clockwise direction, and the burr removing stone 26 engages the knife. During the clockwise turning of the housing, the side 49 of the slot 40 will be moved away from the pin 4|, and there will be a small clearance which allows the spring 42 to act resiliently on the burr stone mounting.

The sharpening mechanism is adapted to be adjusted to compensate for wear of the knife. The sharpening mechanism can be adjusted vertically by sliding the lower end of the pin or spindle I8 in its socket 59, which is formed in the knife bracket I6. Also, the spindle of the sharpener stone 25 can be set or adjusted axially so that the stone will have proper engagement with the knife side during the sharpening operation. After the spindle on the sharpener stone 25 has been axially adjusted, it is locked in its adjusted position by the screw 33. While the new sharpening mechanism is shown mounted on a machine having a manually reciprocated carriage, it is, of course, understood that the sharpening mechanism may be applied to any kind of a slicing machine which employs a rotary knife.

The invention above described provides a compact, efiicient, normally inoperative sharpening means which can be brought into sharpening position by merely giving the housing a clockwise turn, at which time the sharpener stone and the burr removing stone are brought into engagement with the knife. The housing is normally urged in a predetermined direction and held in proper alignment by means of a stop pin. Therefore, as soon as the sharpening operation is to cease, the housing is let go, that is, no manual pressure is applied thereto, at which time the housing will return to its normal initial nonoperative position. The main sharpener stone can be manually controlled to cause the proper grinding action, while the burr removing stone is constantly and resiliently urged into contacting relationship with the opposite side of the knife. The sharpening mechanism is compactly arranged in a housing which has a. cover plate which is instantly removable and easy access to the entry of the housing is therefore assured. The mechanism is adaptable for vertical adjustment on its vertical spindle, and the grinding stone is adaptable for axial adjustment.

The grinding and sharpening mechanism disclosed in Figs. 7 to 14 inclusive vary somewhat from the previously described sharpening mechanism. In these latter figures sharpening mechanism I00 is provided. This sharpening mechanism comprises a vertical threaded shaft or spindle IOI which is slidably mounted in a boss or bearing I02 formed in the knife supporting bracket. The lower end of the shaft or spindle IOI, more clearly shown in Fig. 10, is provided with oppositely disposed vertical grooves I03 and a set screw I04 having a knurled thumb piece I05 threadedly engaging the boss I02 to normally prevent revoluble movement of the shaft or spindle IOI. The end of the set screw I04 is provided with a smooth or pilot end I06 whereby the spindle IN is adapted to have vertical slidable movement in its opening in the boss I02, the smooth pilot end I06 acting as a guide in either of the grooves or slots I03. The spindle IOI is of a reduced diameter as indicated at I 01, the reduced diameter being substantially the same diameter as the distance bevented from rotating by the pilot end I06 in a groove I03. The vertical spindle is adapted to be raised upwardly until the upper surface of the knob I08 engages the lower surface of the set screw I04. At this latter position the smooth pilot end I06 will be at the reduced diameter of the spindle at which time the spindle may be rotated. In Fig. 10 the sharpening mechanism is shown in grinding position as regards the knife I I39, but the normal idle position of the sharpening mechanism is removed from the position shown in Fig. 10 or in the position shown in dotted lines in Fig. 8. When the sharpening mechanism is in its normal idle position, that is, away from the knife, the set screw I94 will engage one of the vertical slots I93,"but when the sharpening mechanism is rotated 180 to knife sharpening position, the set screw will engage the other groove I93 as shown in Fig. 10. In other words, the set screw engages one groove in idle position and engages the other groove in operating position when the sharpening mechanism has been rotated 180 about its vertical axis. To rotate the spindle, however, the spindle must'be raised upwardly until the reduced diam eter I01 is opposite the pilot point We at which time the spindle can be turned until the other groove I03 is in position in respect to the set screw I94 when the spindle is again lowered to bring the mechanism into sharpening position relativeto the knife. A set screw Mo threadedly engages a part of the boss )2 and engages the set screw N34 to hold the set screw I04 in its proper operative locked position and prevent unauthorized removal of the spindle. To remove the spindle from the boss I92 the set screw I I9 is first unscrewed to release its. engagement with the set screw I04. The set screw I99 can then be rotated to move the smooth pilot end out of the path of theknob I98. The locking engagement of the set screw I 59 with the set screw I94 may comprise a point on the end of the set screw III] engaging a groove provided in the set screw I94. A knurled nut HI threadedly engages the shaft or spindle IilI, Fig. 10, and rests upon the top of the boss I92. Rotation of the knurled nut I l I adjusts the sharpening mechanism vertically, and a set screw H2, threadedly engaging the knurled nut IIi, locks the knurled nut III in adjusted position in respect to the shaft or spindle IOI. r

A mechanism support IE2 is arranged inside of the casing II 3, and is fastened to the upper end II4 of the spindle M2 by a set screw i I5, see Fig. 10. The casing I I3 is held in position on the support IIZ by means of the screws HE. A sharpening stone Il'I constitutes the grinding stone for grinding one side of the knife, while a second stone IIB constitutes the burr removing stone and is adapted to engage the other side of the knife.

The sharpening stone II! is mounted on a shoulder spindle II9, see Fig. 9,'being held by a screw I20. The spindle H9 is rotatably assembled in a sleeve I25 which is axially adjustable in a bearing I22 of the mechanism support I I2. The spindle H9 is axially held in the sleeve I2I by a Washer 523 and a screw I24. Ball bearings I25 are provided as indicated in Fig. 9 to permit freerotative movement of the spindle I 59 in the sleeve I2 I A set screw I26 locks the sleeve I2I to the bearing I22 after the sharpening stone II! has been properly adjusted in respect to the knife, and this set screw extends through a slot I2! in the bottom of the bearing I22. A spring IZB-arranged in an annular recess I29 in the sleeve I2I urges the sleeve I2! in a predetermined direction, the movement of the sleeve in respect to the bearing being limited by the slot I21. 7

The burr removing stone H8 is mounted on a shoulder spindle I33,-see Fig. 13, being held by a screw I3I. The spindle I39 is rotatably assembled in a sleeve I32 which is axially adjustable in a bearing I33 of the mechanism support H2. The spindle I39 is axially held in the sleeve I32 by a washer I34 and a screw I35. Ball bearings I36 are provided as indicated in Fig. 13 to permit free rotative movement of the spindle E36 in the sleeve I32. A pin I3! locks the sleeve E3? to the bearing I33 after the burr removing stone IIB has been properly adjusted in respect to the knife, and this pin extends through a slot 533 in the bottom of the bearing I33. A spring I39 arranged in an anuular recess I 49 in the sleeve I32 urges the sleeve I32 in a predetermined direction, the movement of the sleeve in respect to the bearing being limited by the slot I38.

A lever operating member I59 is mounted on the shaft or spindle EIlI, Fig. 11, and is urged in a predetermined direction by a torsion spring I5I, Fig. 10. The spring I5I is stronger than the combined springs I28 and I39 and acts on'the operating .member I59 to urge it in a predetermined direction as shown in Fig. 11. The spring I5I urges the operating member I59 so that the part I52 and the extension I53 thereof will move the members I 31 and I't respectively toward one end of their respective slots as shown in Fig. 11. The torsion spring E5I therefore urges the operating member or lever 59 in a direction against the tension of the springs I 23 and I39 and therefore holds the stones ill and MB inwardly with respect to their bearings and against the tension of the springs I28 and I39. When the operating lever I59 is moved in a direction downwardly as viewed in Fig. 11, from the position shown in that figure to the position shown in Fig. 12, the engaging portion I52 and the extension I53 will be away from the pins 53? and I26 at which time the respective springs of those members will be permitted to act on the stones and the stones will be moved to sharpening position by these springs. will be resiliently urged against the knife. A second lever-I54 may be fastened to a part of the casing and acts as a handle to assist in operating the lever I 59, as a squeezing pressure applied to these two members, will cause the pivotally mounted member R59 to move toward the rigidly mounted lever I54.

The slots I27 and I38 are so positioned and proportioned and the operating lever lEEi is arranged and constructed so that when the operating lever I56 is operated, the grinding stone will engage the knife first immediately followed by the burr removing stone. When the lever l5il is returned to normal position, the grinding stone will disengage the knife and be removed therefrom first, while the burr removing stone will be last to be removed from the knife. In other words, the grinding stone will engage the knife first and be moved away from the knife first, while the burr removing stone will be applied last and removed last. To adjustably cause the operation of the stones just referred, to, a clip G55 may be mounted on the casing. The clip I55 is provided with an elongated slot I55 through which a set screw H51 passes. The movement of the pin I26 in the slot The stones therefore I21 therefore can be regulated by means of the clip I51 as the pin I26 also passes through a second slot formed in the clip I55.

The sharpening mechanism shown in Figs. '7 to 14 inclusive permits the sharpening mechanism to be moved toward and away from the knife a distance sufficient so that any matter on the knife will not come in contact with the stones during normal cutting operation of the knife. Also, parts of meat, grease, etc., will be prevented from being thrown up into the casing and engaging the stones. When it is desired to sharpen the knife, the entire mechanism is rotated 180 to sharpening position. When the lever I is operated, the stones are brought into grinding relationship with the knife. After the grinding operation the mechanism is returned to its normal out-of-the-way position.

Either of the above mechanisms may be employed in connection with the structure shown and disclosed in the copending application, Serial No. 718,583, filed April 2, 1934, and assigned to the present assignee.

In one embodiment of the present invention herein shown, the sharpening stones may be brought into grinding relation by twisting the housing to force the grinding stone into engagement with the knife. However, such turning movement will cause turning movement of the stone also, therefore the stone will not move in a straight line because it is given a turning movement. due to the turning or twisting of the casing. In another embodiment herein shown both stones move in a straight line, but the housing is not turned, the parallel movement of the stones being caused by the operation of the handle I50, Figs. 11 and 12. In another copending application filed by Stukart, Serial No. 729,749, filed June 9, 1934, and assigned to the present assignee, the housing is twisted but the stones still move in a straight line, the turning or twisting movement of the' housing merely freeing the stones to permit them to move in a straight line.

The invention just described permits resilient engagement of the stones on the knife, allows. the stones to be kept clean and provides mechanism which can be readily and economically manufactured.

Changes may be made in the form, construction and arrangement of the parts without departing from the spirit of the invention or sacrificing any of its advantages, and the right is hereby reserved to make all such changes as fairly fall within the scope of the following claims:

What I claim as new and desire to secure by Letters Patent, is:

1. In a sharpening mechanism for slicing machines having a rotary knife, a housing, grinding members mounted in the housing on opposite sides of the knife, means for yieldingly moving the grinding members to the knife, a spring pressed lever for normally compressing the yieldingly moving means to hold the grinding members out of contact with the knife, and a fixed arm mounted substantially parallel with the spring pressed lever in position to permit manual grasping of the lever and arm to press the lever toward the arm against the tension of its spring to permit the grinding members to be gradually moved to the knife by the yieldingly moving means, the spring pressed lever being returned to its normal position by its spring when the manual pressure is removed.

2. A sharpening mechanism for slicing machines having a rotary knife, comprising a spindle having a pair of slots therein operatively connected, sharpening mechanism mounted on said spindle and arranged on one side of the knife, fixed means for engaging the slots whereby the spindle is normally prevented from rotating, said fixed means having relatively sliding movement with the slots and permitting the spindle to be rotated when it is raised a predetermined distance for bringing the mechanism into or out of sharpening engagement with the knife at will, yielding means to force the sharpening elements against the knife, a spring pressed lever mounted between said yielding means for compressing the yielding means and thereby normally hold the sharpening elements away from the knife, said lever being adapted for manual operation to relieve compression of the yielding means and permit said yielding means to force the sharpening elements against the knife, and a fixed rest mounted substantially parallel with the lever to permit manual grasping of the lever and rest whereby a steady movement of the lever may be facilitated.

3. A sharpening mechanism for slicing machine knives comprising a casing, grinding stones mounted in the casing on opposite sides of the knife, spring means urging the grinders toward the knife, a spring pressed lever normally preventing the urging action of the grinders from becoming effective, said lever, when operated against the tension of its spring, releasing said spring means and permitting the spring means to become effective whereby the grinders will be urged into sharpening position with the knife, and a rest mounted substantially parallel to the lever for convenient manual grasping of the lever and rest to move the lever toward the rest to release said spring means.

JOSEPH FOLK. 

